RingCentral has been a leader in the cloud phone services business for a few years, and it claims to serve more than 300,000 businesses across a wide array of industries, including health care, finance, legal, retail, and real estate.

RingCentral named former WebEx exec David Berman as its president in mid-June with the purpose of helping the company look at either going public or being acquired. It appears that going public is the course the company has set itself on with this filing.

The S-1 filing states that RingCentral will apply for listing its Class A common stock under the symbol “RNG.” Goldman Sachs, J.P. Morgan, and Bank of America are listed as joint book-running managers for the proposed offering.

RingCentral points out that its revenues have increased steadily each year, with total revenue of $50.2 million in 2010, $78.9 million in 2011, and $114.5 million in 2012. Yet the company has yet to be profitable. It incurred net losses of $7.3 million, $13.9 million, and $35.4 million, in 2010, 2011, and 2012.

Most recently, the company states that it generated $73.2 million in revenue during the first six months of 2013. But it took a $23.9 million loss for the same period.

While RingCentral has clearly grown and has a ton of reach with its 300,000 customers, it still outlines a lot of risks for potential investors:

Significant Losses: We have incurred significant losses in the past and anticipate continuing to incur losses for the foreseeable future, and we may therefore not be able to achieve or sustain profitability in the future.

Limited Operating History: Our limited operating history makes it difficult to evaluate our current business and future prospects, which may increase the risk of your investment.

Reliance on Third Parties: We rely on third parties for all of the network connectivity that is needed to deliver our services. We also lease third-party co-location facilities to house our data centers. We use purchased or leased hardware and licensed software from third parties, as well as rely on third parties for some software development, quality assurance, operations and customer support.

Third-Party Facilities Risks: Interruptions or delays in service from our third-party data center hosting facilities and co-location facilities could impair the delivery of our services and harm our business.

Security Risks: A security breach could delay or interrupt service to our customers, harm our reputation or subject us to significant liability.

Interruptions of Services: Interruptions in our services, whether caused by us or third parties, could harm our reputation, result in significant costs to us and impair our ability to sell our services.